SCIENCE & TECHNOLOGY
Saturn’s Moon Titan
News: Lakes filled with liquid methane spotted on Saturn’s moon Titan.
Source: The Hindu
Prime lakeside property in the northern polar region of Saturn’s moon Titan - if you like lakes made of stuff like liquid methane.
Using data obtained by NASA’s Cassini spacecraft before that mission ended in 2017 with a deliberate plunge into Saturn, the scientists found that some of frigid Titan’s lakes of liquid hydrocarbons in this region are surprisingly deep while others may be shallow and seasonal.
Titan and Earth are the solar system’s two places with standing bodies of liquid on the surface. Titan boasts lakes, rivers and seas of hydrocarbons: compounds of hydrogen and carbon like those that are the main components of petroleum and natural gas.
The researchers described landforms akin to Mesas towering above the nearby landscape, topped with liquid lakes more than 300 feet deep comprised mainly of methane. The scientists suspect the lakes formed when surrounding bedrock chemically dissolved and collapsed, a process that occurs with a certain type of lake on Earth.
The scientists also described “phantom lakes” that during wintertime appeared to be wide but shallow ponds — perhaps only a few inches deep — but evaporated or drained into the surface by springtime, a process taking seven years on Titan.
The findings represented further evidence about Titan’s hydrological cycle, with liquid hydrocarbons raining down from clouds, flowing across its surface and evaporating back into the sky. This is comparable to Earth’s water cycle.
Because of Titan’s complex chemistry and distinctive environments, scientists suspect it potentially could harbor life, in particular in its subsurface ocean of water, but possibly in the surface bodies of liquid hydrocarbons.
Titan, with a diameter of 5,150 km, is the solar system’s second largest moon, behind only Jupiter’s Ganymede. It is bigger than the planet Mercury.
Titan is the largest moon of Saturn and the second-largest natural satellite in the Solar System. It is the only moon known to have a dense atmosphere, and the only object in space, other than Earth, where clear evidence of stable bodies of surface liquid has been found.
Titan is the sixth gravitationally rounded moon from Saturn. Frequently described as a planet-like moon, Titan is 50% larger than Earth's moon and 80% more massive. It is the second-largest moon in the Solar System after Jupiter's moon Ganymede, and is larger than the planet Mercury, but only 40% as massive. Discovered in 1655 by the Dutch astronomer Christiaan Huygens, Titan was the first known moon of Saturn, and the sixth known planetary satellite (after Earth's moon and the four Galilean moons of Jupiter). Titan orbits Saturn at 20 Saturn radii. From Titan's surface, Saturn subtends an arc of 5.09 degrees and would appear 11.4 times larger in the sky than the Moon from Earth.
Titan is primarily composed of ice and rocky material. Much as with Venus before the Space Age, the dense opaque atmosphere prevented understanding of Titan's surface until the Cassini–Huygens mission in 2004 provided new information, including the discovery of liquid hydrocarbon lakes in Titan's polar regions. The geologically young surface is generally smooth, with few impact craters, although mountains and several possible cryovolcanoes have been found.
A joint endeavor of NASA, the European Space Agency, or ESA, and the Italian Space Agency, Cassini launched in 1997 along with ESA's Huygens probe. The spacecraft contributed to studies of Jupiter for six months in 2000 before reaching its destination, Saturn, in 2004 and starting a string of flybys of Saturn's moons. That same year it released the Huygens probe on Saturn's moon Titan to conduct a study of the moon's atmosphere and surface composition. In its second extended mission, Cassini made the first observations of a complete seasonal period for Saturn and its moons, flew between the rings and descended into the planet's atmosphere.